This invention relates to an apparatus for fusing a plastic fitting to a plastic pipe. A known means of attaching a thermoplastic component to a thermoplastic pipe is by heat fusion. The term "heat fusion" as used herein means heating mating surfaces of a fitting and a portion of the exterior surface of a plastic pipe and while these surfaces are in molten states, to join the surfaces together under applied pressure and holding pressure against the components until the joined surfaces cool and thereby fuse to each other.
The butt fusion of one length of plastic pipe to another is a well known technique. This invention relates not to butt fusion wherein one length of pipe is joined to another but to the fusion of a fitting to the sidewall of a plastic pipe. For this purpose, an apparatus is attached to the pipe to afford means of positioning a fitting in proper relationship to the pipe and to move the fitting and the pipe into engagement with each other while heated surfaces cool to fuse the fitting and the pipe together.
For background information relating to the attachment of fittings to the sidewall of a plastic pipe, reference may be had to the following previously issued United States Patents:
______________________________________ U.S. PAT. NO. INVENTOR TITLE ______________________________________ 3,616,024 Windle Method and Apparatus For Welding Heat Sealable Pipes 3,743,566 Louthan et al Apparatus For Joining A Plastic Fitting To A Plastic Pipe 4,338,712 Dearman Welding Fixture For Use In Joining Two Tubular Members 4,445,677 Hansen et al Clamping Apparatus For Plastic Pipe 4,533,424 McElroy Pipe Fusion Apparatus With Load Cell For Attaching Side Wall Fittings ______________________________________